1. Field of Invention
The present invention relates to a gas generator suitable for airbag systems installed in automobiles and occupant restraining devices for use in pedestrian protection devices.
2. Description of Related Art
In order to accurately control combustion of a gas generating agent, a device has been made such that a combustion surface area and an amount of generated gas is controlled by molding a gas generating agent into a single-perforated shape, pellet or disk.
In the gas generator disclosed in JP-A No. 2002-204947, the gas generating agent burns from end surface. Thus, by igniting the end surface of the gas generating agent with an igniter, the end surface combustion proceeds in the direction shown by the arrow in FIG. 1, the generated gas is released from the circulation hole via a flow rate control valve into a gas circulation tube and ejected from the gas circulation tube to the outside. In such a gas generator, the combustion is started by an igniter 11. The igniter 11 is disposed opposite to the combustion end surface (exposed end surface) 10a of the gas generating agent 10, and the size of the ignition portion of the igniter 11 is small by comparison with the area of the combustion end surface 10a. 